Optical networks employing wavelength division multiplexing (WDM) are now a viable technology for implementing a next-generation network infrastructure that will support a diverse set of existing, emerging, and future applications. WDM bridges the gap between the lower electronic switching speeds and the ultra high transmission speeds achievable within the optical medium. WDM divides the enormous information carrying capacity of a single mode fiber into a number of channels, each on a different wavelength and operating at the peak electronic speed, making it possible to deliver an aggregate throughput on the order of terabits per second. As such, WDM is the solution of choice for providing a faster networking infrastructure that can meet the explosive growth of networking, and in particular, the Internet, in the near future.
WDM technology initially was deployed in point-to-point links and has also been extensively studied, both theoretically and experimentally, in wide area or metropolitan area distances. A number of WDM local area testbeds have also been implemented or are currently under development.
While optical communication links are common in core and metropolitan networks, the progress has been slower in the area of access and especially local area networks (LANs). The telecom industry, in general, prefers to accept traditional LAN concepts. In this regard the industry is more likely to expand on the success of a bus-based broadcast network, such as Ethernet by adopting new standards thereof, for example GigE (Gigabit Ethernet) and 10 GigE (10 Gigabit Ethernet) standards.
Industry reluctance has been fueled by many factors, including the reality that an all-optical LAN requires a completely new set of components, such as tunable lasers, tunable filters, passive star couplers and the like. These devices have only recently matured, in terms of technological advancement and cost effectiveness, to the point where implementation of such devices at the LAN level can be effectively and cost-efficiently realized. Thus, the need exists to develop a dense WDM (dWDM), all-optical architecture for a local area network and an accompanying signaling protocol to facilitate communications between nodes in the all-optical local area network.